The old adage says “money can’t buy you happiness,” but a new study has proved otherwise.

Scientists at the University of Cambridge have confirmed that it’s not how much cash you have, but how you spend it.

In collaboration with a large international bank, researchers surveyed more than 600 customers with established personality questionnaires and life satisfaction measures. They also looked at more than 76,800 transactions from 625 participants over six months to study people’s spending behavior.

It turned out those whose purchases better fit their personal motivations and needs were generally happier and more satisfied with their lives.

“Decades of research have shown that money, per se, does not necessarily lead to greater happiness and life satisfaction,” study author Sandra Matz said. “However, we suggest it can indeed buy happiness if we spend 'right.' By that, we mean spending money on something that allows us to maintain a lifestyle that is in line with our most fundamental psychological motivations.”

To show the relationship between personality-matched consumption and happiness is, indeed, a causal one. Scientists ran a follow-up experiment. They asked groups of extroverted and introverted students to spend voucher money either at a student bar or in a book store.

Results showed that extroverts were happier to spend time in the bar where they could socialize, whereas introverts chose to spend the time alone reading a book.

“We spend very little time thinking about how we can use the money we have in a way that benefits our happiness,” Matz added. “Our research suggests that instead of just buying stuff that our friends have bought or that our impulsivity leads us to buy, we should ask ourselves whether it will actually help us to lead the lifestyle that we want.”

In the future, scientists want to discover why some people are better than others at spending money in a way that fits their personality.

For example, people with a very low income simply do not have the luxury to spend their money on products that suit them. Similarly, those who are highly dependent on the opinions of others try to buy things that make them “look good” but in doing so, aren’t meeting their personal motivations.

“We are eager to find new opportunities to find large-scale datasets to further prove these ideas,” Matz concluded.